Device for sharpening pencils



Obt- 13, 1925- 4 J. J. BGHM DEVICE FOR SHARPENING PENCILS Filed July 7. 1924 Patented Oct. 13, 1925.

UNITED STATES 1,556,669 PATENT OFF-ICE.

. T JOHANN JVAKOB 3611M, 0E ZURICH SWITZERLAND...

3 DEVICE ron-snaarnm'ne PENCILS.

' vApplication flied :nu r,

To all whom it may concern:

Be it known that I, J OHANN J AKOB BoHM, engineer, a citizen of the Austrian Republic, residing at Stafielstrasse 2', Zurich, Switzerland, have invented certain new and useful Improvements in Devices for Sharpening Pencils, of which the following is a specification.

The present invention relates to a new and improved device for sharpening pencils in which the pencil is slowly rotated whilst pressed against a rotating disk of abrasive material. The object of the invention is to provide a pencil sharpener of the character described in which the lead of the pencil will be preserved from breaking by the suitable elastic construction of the abrasive disk.

Another object of my invention is to provide a pencil-sharpener in which the pressure acting to force the pencil against the abrasive disk may be adjusted by hand.

Other features of my invention will be set forth in the description and appended claims.

In the drawings the preferred embodiment of my invention is shown by way of an example Fig. 1 is a sectional elevation of the pencil-sharpener.

Fig. 2 is a section on line A-B of Fig. 1.

Fig. 3 is a section on line OD of Fig. 1.

Figs. 4 to 6 show pencils with different shapes of the point.

The new device comprises a casing 1 having a flange 2 with holes through which may be passed screws by means of which the pencil-sharpener may be screwed firmly to a suitable support, etc. In the lower part of the casing 1 is slidably fitted'a drawer 3 in which is collected the material abraded from the pencil. In the casing 1 a spindle 4 is rotatably mounted, said spindle 4 is provided with teeth 5. The lower end of s indle 4 rests on an arm 6 fixed to a shaft% and having a lug 6" arranged to bear against one side of the casing. Shaft 7 is rotatably mounted in the casing 1 and is provided with a handle 30 by means of which the shaft 7 may be turned against the action of a spring 8 encircling said shaft'7. One end of the spring 8 is fastened to the shaft 7 the other to the casing 1, the spring has the tendency to hold arm 6 in the position shown in Fig. 1. The upper end-of shaft 4 projects into a chamber 9 closed by a removable cover 10 comprising a glass disk 11. Within 1924.. I Serial in. 724,680.

the chamber 9 a dished or conical disk 12 is mounted on the spindle 4 and said disk 12 supports a plate 13 of resilient yielding or elastic material such as felt, india-rubber core etc. On the plate 13 rests a circular sheet 14 of abrasive material for instance of flint-paper or, the like. The parts 12, 13, 14 are secured to the spindle 4 by means of a thumb nut 15 and a washer 16 in such a manner that the said parts partake on the rotations of spindle 4. With the teeth 5 of spindle 4 a spur wheel 17 is in mesh which comprises a toothed conical gear 18. .A second bevel gear 19 is in mesh with said gear 18. The gear 19 is rigidly connected to a spur wheel 20-and to a horizontal shaft 21 rotatably journalled in the casing 1. To the shaft 21 a crank 22 with handle 23 is rigidly connected. The gear 20 is in mesh with a toothed gear 24 rigidly fixed to a sleeve 25' rotatably mounted in a socket 26 of the chamber 9 (Fig. 3). The sleeve 25 is secured by a screw 29 of the casing 1 engaging a groove 30 of sleeve 25. The axis of said sleeve 25 runs tangent to a circle concentric to spindle 4 and at an angle to disk 14. Within the sleeve 25 three jaws 26 are arranged adapted to grip the pencil to be sharpened. Said jaws 26 may be pressed on the pencil 27 by means of a nut 28 screwed on the sleeve 25.

The operation of the device is obvious. The pencil 27 is inserted between the jaws 26 by screwing up the nut 28 the jaws 26 firmly grip the pencil. By rotating the crank 22 the sleeve 25 is slowly turned and shaft 4 at a. much higher speed. The disk 14 runs preferably in a direction shown by arrow Fig. 4. According to the position given to the pencil 27 with reference to the disk 14 the point on the pencil is taller or shorter. The disk 14 can be pressed on to the pencil by means of the handle 30 which is turned against the action of the spring 8. The arm 6 lifts the spindle 4 which remains in engagement with the gear 17. The rotating disk 14 being pressed on the pencil abrades the wood etc. and a point is produced. The disk 14 being cushioned does not break the lead of the pencil and very sharp points of any desired length may be produced.

lVhat I wish to secure by U. S. Letters Patent is: g

1. In a pencil sharpener a casing, rotatable pencil holding means journaled in said casing, a spindle journaled in said casing, a disk of abrasive material on said spindle, means to move the spindle endWise and common rotating means for the pencil h0lding means and the pencil sharpening'means.

2. In a pencil-sharpener, a casing, rotatable pencil-holding means journaled in said casing, a spindle journaled in said casing, a disk of abrasive material exchangeably mounted on said spindle, an elastic support 10 for said disk, an arm supporting said spindle and fixed to a shaft, a hand lever fixed to said shaft adapted to shift the disk carrying spindle in its axial direction, and means to rotate said pencil holding means and said 1 pencil sharpening means.

In testimony whereof I affix my signature.

J OH. BGHM. 

